首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   4501篇
  免费   359篇
  国内免费   16篇
耳鼻咽喉   33篇
儿科学   89篇
妇产科学   64篇
基础医学   654篇
口腔科学   91篇
临床医学   539篇
内科学   903篇
皮肤病学   49篇
神经病学   483篇
特种医学   225篇
外科学   595篇
综合类   51篇
一般理论   11篇
预防医学   558篇
眼科学   47篇
药学   271篇
中国医学   14篇
肿瘤学   199篇
  2023年   36篇
  2022年   71篇
  2021年   122篇
  2020年   85篇
  2019年   121篇
  2018年   140篇
  2017年   104篇
  2016年   123篇
  2015年   155篇
  2014年   165篇
  2013年   233篇
  2012年   363篇
  2011年   362篇
  2010年   211篇
  2009年   170篇
  2008年   298篇
  2007年   268篇
  2006年   222篇
  2005年   236篇
  2004年   226篇
  2003年   182篇
  2002年   216篇
  2001年   71篇
  2000年   59篇
  1999年   58篇
  1998年   40篇
  1997年   26篇
  1996年   23篇
  1995年   18篇
  1994年   21篇
  1993年   13篇
  1992年   48篇
  1991年   40篇
  1990年   44篇
  1989年   27篇
  1988年   26篇
  1987年   30篇
  1986年   15篇
  1985年   23篇
  1984年   16篇
  1983年   9篇
  1982年   10篇
  1981年   8篇
  1980年   11篇
  1979年   11篇
  1978年   11篇
  1977年   8篇
  1974年   10篇
  1973年   13篇
  1972年   9篇
排序方式: 共有4876条查询结果,搜索用时 15 毫秒
41.
Study ObjectiveTo evaluate the safety and efficacy of sugammadex for reversal of rocuronium-induced neuromuscular blockade in patients with pulmonary disease.DesignPhase III, randomized, multicenter, parallel-group, comparative, safety-assessor blinded study.SettingNine hospital sites.Patients77 ASA physical status 2 and 3 patients, aged ≥ 18 years, with a history of pulmonary disease, and scheduled for surgery with general anesthesia requiring neuromuscular blockade.InterventionsFollowing anesthesia induction, patients received rocuronium 0.6 mg/kg with 0.15 mg/kg maintenance doses as needed. Patients were randomized to receive sugammadex 2 mg/kg or 4 mg/kg after the last rocuronium dose at reappearance of the second twitch.MeasurementsSafety evaluations included adverse events, laboratory parameters, vital signs, and evidence of recurrent or residual neuromuscular blockade. Efficacy was evaluated as the time from sugammadex administration to recovery of the train-of-four (TOF) ratio to ≥ 0.9.Main ResultsSafety was comparable between doses, with no evidence of residual or recurrent neuromuscular blockade. Two bronchospasm cases were reported (4 mg/kg group), both in patients with asthma who received desflurane for anesthesia maintenance. Geometric mean (95% confidence interval) times to a TOF ratio of ≥ 0.9 were 2.1 (1.7 - 3.1) min (2 mg/kg) and 1.8 (1.5 - 2.7) min (4 mg/kg).ConclusionSugammadex 2 mg/kg and 4 mg/kg were well tolerated and effective in patients with a history of pulmonary disease. Bronchospasm is a possibility when administering sugammadex to patients with underlying pulmonary disease.  相似文献   
42.
43.
44.
Modern bone densitometry systems using dual-energy X-ray absorptiometry (DXA) automatically analyze lumbar spine scans and provide clinically important information concerning spine bone mineral density (BMD) and fracture risk. Lumbar spine BMD accurately reflects skeletal health and fracture risk in most cases, but degenerative diseases associated with aging may lead to the formation of reactive bone (osteophytes) and other confounding conditions that elevate BMD without a concomitant increase in bone strength or decrease in fracture risk. Automated densitometry software known as computer-aided densitometry (CAD) (GE Medical Systems Lunar) assists the user in identifying scans with common acquisition and analysis irregularities known to influence BMD values. Visual examination of 231 female spine scans measured with DXA found abnormal conditions that could influence BMD results in 29% of scans. The sensitivity and specificity of several criteria for identifying scans with conditions that could influence BMD were determined. A good criterion for identifying scans with abnormal conditions was a T-score difference of greater than 0.9 or 1.0 between L1-L4 mean and individual vertebrae. Criteria for excluding affected vertebrae were determined. Exclusion of affected vertebrae resulted in a mean BMD decrease of nearly 0.6 SD (T-score) among affected scans.  相似文献   
45.
Arterio-ureteric fistulae are rare but can be associated with significant morbidity and mortality. We describe a novel case in which an arterio-ureteric fistula occurred as a complication following external iliac artery angioplasty and stenting, in a patient who had undergone previous pelvic surgery, radiotherapy, ureteric stenting, and urinary diversion surgery. Prompt recognition enabled successful endovascular management using a covered stent.  相似文献   
46.
The patient's own palm is used as a template in assessing small patchy burns and is traditionally believed to be 1% of body surface area. This does alter with the patient's age, sex and BMI and there have been suggestions that it can also differ between ethnic groups. We undertook this study to see if there were any differences in the hand surface area between Caucasians, Orientals and Asians. It was done by tracing the hand outline and calculating the surface area. The study showed that there was no significant difference between the three ethnic groups in terms of hand surface area.  相似文献   
47.

Background Context

The results of meta-analyses are frequently reported, but understanding and interpreting them is difficult for both clinicians and patients. Statistical significances are presented without referring to values that imply clinical relevance.

Purpose

This study aimed to use the minimal clinically important difference (MCID) to rate the clinical relevance of a meta-analysis.

Study Design

This study is a review of the literature.

Patient Sample

This study is a review of meta-analyses relating to a specific topic, clinical results of cervical arthroplasty.

Outcome Measure

The outcome measure used in the study was the MCID.

Methods

We performed an extensive literature search of a series of meta-analyses evaluating a similar subject as an example. We searched in Pubmed and Embase through August 9, 2016, and found articles concerning meta-analyses of the clinical outcome of cervical arthroplasty compared with that of anterior cervical discectomy with fusion in cases of cervical degenerative disease. We evaluated the analyses for statistical significance and their relation to MCID. MCID was defined based on results in similar patient groups and a similar disease entity reported in the literature.

Results

We identified 21 meta-analyses, only one of which referred to MCID. However, the researchers used an inappropriate measurement scale and, therefore, an incorrect MCID. The majority of the conclusions were based on statistical results without mentioning clinical relevance.

Conclusions

The majority of the articles we reviewed drew conclusions based on statistical differences instead of clinical relevance. We recommend introducing the concept of MCID while reporting the results of a meta-analysis, as well as mentioning the explicit scale of the analyzed measurement.  相似文献   
48.

Objective

Little is known about the outcomes of aortic root operations that involve inducing hypothermic circulatory arrest for relatively extensive proximal aortic surgery. We attempted to identify predictors of postoperative hospital length of stay (LOS) and factors that affect postoperative recovery.

Methods

During 2006-2014, 247 of 265 patients (93.2%) with disease extending into the aortic arch survived aortic root operations (206 elective, 41 urgent/emergent) in which hypothermic circulatory arrest with moderate hypothermia was used. Stepwise multivariate regression analysis was performed to identify predictors of LOS (as a continuous variable) and prolonged LOS (defined as LOS >9 days, the median for the cohort). By this definition, 111 patients (45%) had prolonged LOS and 136 (55%) did not.

Results

Preoperative factors that independently predicted longer LOS in the entire cohort included age (P = .0014), redo sternotomy (P = .0047), and intraoperative packed red blood cell (PRBC) transfusion (P = .0007). Redo sternotomy and intraoperative PRBC transfusion also predicted longer LOS in 3 subgroup analyses: one of elective cases, one from which total arch replacement procedures were excluded, and one limited to patients who were discharged home. Age predicted longer LOS in the non-total arch (hemiarch) replacement patients. Ventilator support >48 hours (P < .0001) was associated with longer LOS. Elective aortic valve?sparing root replacement predicted a shorter LOS than valve replacement in multivariate regression analysis (P = .028).

Conclusions

In patients undergoing aortic root surgery with hypothermic circulatory arrest for disease extending into the aortic arch, reducing intraoperative PRBC transfusion except when absolutely necessary may reduce postoperative LOS and expedite recovery. Performing aortic valve–sparing root replacement, when feasible, may also reduce LOS.  相似文献   
49.
The aim of this dry bone study was to determine the range of hip motion to impingement for different hip resurfacing cup positions and component sizes. The maximum angles of hip flexion, extension, abduction, and adduction were calculated from 3-dimensional coordinates for: 1. Cup inclination of 30 degrees , 40 degrees , 50 degrees , 60 degrees , and 70 degrees with fixed anteversion; 2. Cup anteversion of 0 degrees , 10 degrees , 25 degrees , 35 degrees , and 45 degrees with fixed inclination; and 3. 3 different component sizes on the same size dry bones. An acetabular component inclination of 50 degrees and an anteversion of 25 degrees allowed the most physiologic range of hip motion. A larger-diameter femoral component relative to the native femoral neck diameter resulted in a greater range of hip motion to impingement.  相似文献   
50.
Epidermolysis bullosa simplex (EBS) is a rare skin disease usually inherited in an autosomal dominant pattern. EBS is resulting from mutations in keratin 5 (KRT5) and keratin 14 (KRT14) genes encoding the keratins 5 and 14 proteins expressed in the keratinocytes of the basal layer of the epidermis. To date, seven pathogenic mutations have been reported to be responsible for EBS in the Canadian population from the province of Quebec: p.Pro25Leu, p.Leu150Pro, p.Met327Thr and p.Arg559X in KRT5; p.Arg125Ser, p.Ile377Thr and p.Ile412Phe in KRT14. Here, we present a novel French-Canadian patient diagnosed with EBS confined to the soles but presenting a severe complication form including blisters, hyperkeratosis, skin erosions and toenail abnormalities. Mutation screening was performed by direct sequencing of the entire coding regions of KRT5 and KRT14 genes and revealed the previously reported missense heterozygous mutation c. 1130T > C in KRT14 (p.Ile377Thr). Furthermore, this patient is carrying a second mutation in KRT5, c.413G > A (p.Gly138Glu), which has been linked to an increased risk of basal cell carcinoma in the literature. We suspect an impact of the p.Gly138Glu variant on the EBS phenotype severity of the studied patient. The pathogenicity and consequences of both genetic variations were simulated by in silico tools.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号